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The objective of this trial was to evaluate the effects of diet and cooling in the holding pen before milking on rectal temperature, respiration rate and milk production and composition. Fifty-eight lactating Holstein cows were used in a factorial split-plot design, at Rafaela Experimental Station from 12 January to 3 March 2003. The treatments were combinations of two diets: control (CD) and balanced (BD) with two levels of cooling before milking: none (NSF) and a sprinkler and fans (SF). Forage:concentrate ratios for CD and BD were 81:19 and 68:32, respectively. Cows were milked twice daily. Milk production was recorded daily, and milk composition (fat, protein, lactose and urea) was analysed twice a week. The physiological data were recorded once a week, before the cattle entered the holding pen and after milking, in the afternoon. Average maximum weekly temperature humidity index was 75.4 and ranged from 61.4 to 83. There were highly significant effects of cooling on physiological responses. Milk production was affected by diet and cooling, with no interaction; the highest and lowest production of milk was 22.42 and 20.07 l/cow per day, for BD+SF and CD+NSF, respectively. Protein was affected by diet, and was higher for BD (3.17 vs. 3.08%). There were interaction effects on milk fat at the 8% level, the highest concentration being 3.65% for BD+NFS. It was concluded that under grazing conditions, cooling by sprinkler and fans before milking improves the comfort of dairy cows, and that the effects on milk production and composition are enhanced when diets are specially formulated for heat-stress periods.

The type of hemodialysis vascular access (fistula, graft, catheter) employed plays an important role in the results of dialysis treatment. Moreover, different complications can affect the vascular access and interfere with the morbidity and mortality of patients.The ideal vascular access is the Cimino Brescia fistula. Graft and catheter methods should be considered as “second choice” because they present a higher incidence of complications, mainly due to thrombosis and infections. Finally, in elderly patients the vascular bed is frequently damaged and this may make it difficult to create a Cimino Brescia fistula.In a 5-year period, 140 elderly patients (>65 years) and 63 “young” patients (< 65 years) started dialysis treatment in our facility. In the elderly group, a native fistula was created in 88% of cases, whereas in the younger patients the percentage was 94% (p: NS). The grafts were, respectively, 11% in elderly and 6% in young patients. Only in one case, in one elderly patient, was a permanent catheter the first vascular access.We also report survival rate of the first vascular access, the incidence of thrombosis, and the need for creating another type of access.We suggest that a native fistula can be easily created in elderly patients and a “second choice” access should be limited to a small proportion of patients.

To clarify the role of chronic anaemia in the pathogenesis of the left ventricular hypertrophy (LVH) of chronic uraemia, nine normotensive dialysed patients were studied before and 3 and 6 months after start of intravenous treatment with recombinant human erythropoietin (rHuEpo). M-Mode echocardiographic estimations of left ventricular mass indices (LVMi) and plasma noradrenaline determinations were made at 3 and 6 months, and total blood volume (TBV) only at 6 months. Resting haemoglobin values were 5.9±1.3 (SD) g/dl, increased within 3 months to 10.2±1.2 (P<0.001), then remained unchanged. Baseline LVMi was 115±18 g/m2 body surface area (b.s.a.) and decreased significantly (P<0.0025) over the entire period to a final value of 78±13 g, which did not differ from the average value for 19 healthy controls. Resting plasma noradrenaline was 1.45±0.44 pmol/ml and did not change significantly, although values were reduced at the 3rd month, when decreased heart rates and slightly and non-significantly increased blood pressures were recorded. TBV did not vary because the increased erythrocyte mass was compensated for by parallel decreases in plasma volume. These data demonstrate the existence of a cause-effect relationship between uraemic anaemia and LVH, although the precise mechanism remains unknown. Amelioration of anaemia with rHuEpo, by allowing recovery from the attendant LVH, might improve longterm cardiovascular prognosis in some dialysed uraemic patients.